[0001] The present invention relates to a lighting luminaire using only one light source
for LCD module and forming method thereof, which is effective in obtaining uniform
light distribution with low power consumption.
[0002] There are a plurality of light source elements contained in a conventional LCD lighting
luminaire. Those lighting elements to be used as a light source are disposed around
the inner edges of the lighting luminaire to emit light rays, while a patterned plate
is provided at the inner surface of the luminaire to function as a reflector. As the
light source is turned on, the emitted light rays are reflected by the patterned reflector
and outputted to desired directions according to the pattern on the reflector plate
thereof.
[0003] As the nature of a lighting element is a point light source whose light intensity
is strongest in the forwards direction, but there are almost no light rays emitted
to other directions. If there is no properly designed lighting luminaire to be associated
with a light source disposed at the center position of the lighting luminaire, it
is impossible to obtain a desired uniform light distribution from a planar light source
by using only one lighting element. If a plurality of lighting elements or electro-luminesence
lamp are employed to obtain uniform lighting effect from a planar light source, there
is other problems of high power consumption and electromagnetic interference.
[0004] In order to solve the above mentioned problems, the present inventor carried out
theoretical studies and simulating experience. Based on these studies and researches,
the present inventor came to propose the present invention.
[0005] It is an object of the present invention to provide a lighting luminaire using only
one light source instead of using four lighting elements or more in a conventional
practice so as to save power consumption and eliminate electromagnetic interference.
[0006] It is another object of the present invention to provide a lighting luminaire using
only one light source wherein ununiformity of light distribution of the lighting luminaire
is further improved by forming several ramps along the inner edge of the lighting
luminaire.
[0007] It is one more object of the present invention to provide design method of this lighting
luminaire.
[0008] These and other objects of the present invention can be achieved by providing a lighting
luminaire comprising a light conducting frame; a unit lighting element disposed at
a position near one comer of the light conducting frame, to function as a point light
source; and a reflector plate provided at the rear surface of the light conducting
frame. A specially designed pattern is formed on the rear surface of the light conducting
frame according to an area distribution function by laser processing or plastic ejection
process. Moreover, several ramps are formed along the inner edge of the light conducting
frame so as to further improve uniform distribution of output light.
[0009] For fuller understanding of the nature and objects of the invention, reference should
be made to the following detailed description taken in conjunction with the accompanying
drawings.
Fig. 1 is a front view of a lighting luminaire using only one lighting element in
a first embodiment of the present invention;
Fig. 2 is a side view of Fig. 1;
Fig. 3 is a rear view of Fig. 1;
Fig. 4 is a drawing showing the state of light tracks of Fig. 1;
Fig. 5 is a front view of a lighting luminaire using only one lighting element in
a second embodiment of the present invention.
[0010] Referring to Figs. 1 through 4 simultaneously, the lighting luminaire of the present
invention comprises a light conducting frame 8; a unit lighting element 26 disposed
at a position near one comer of the light conducting frame 8, to function as a point
light source; and a reflector plate (not shown) provided at the rear surface of the
light conducting frame 8. The emitted light from the point light source. i.e. lighting
element 26 is conducted into the lighting luminaire along an extended structure of
the light conducting frame 8 in diffused state before being outputted. A specially
designed pattern 11 is formed on the rear surface of the light conducting frame 8
in accordance with an area distribution function by laser processing, or plastic injection
process, or printing process, or extrusion process, or mechanical or exposure processing
(see Fig. 3). The form of mesh distribution in this pattern 11 is different from that
according to conventional techniques in the way that variation of mesh density of
the pattern 11 is in a defined relation with a main axis along a line forming an angle
α with the horizontal line (x-axis) assuming point light source 26 is located at the
origin of coordinate. The value of α is generally 20°∼70°. Several ramps 12, 14, 16,
22, 24 are formed along the inner edge of the light conducting frame 8 so as to capture
and reflect the biased light rays into effective directions 13, 15, 17, 23, 25, etc.
thereby eliminating unlighted dark space as shown in Figs. 3 and 4. In this version
the lighting luminaire of the present invention is able to become a uniform planar
light source. The tilted angle of ramps is variable from 5° to 60° depending on the
contour and dimension of the lighting luminaire.
[0011] In an embodiment of the present invention shown in Fig. 1, the meshes formed by sand
spraying gradually from sparse and dense away from the point light source are finer
than being formed by etching such that the fine meshes can serve to prevent the light
from random reflection during proceeding to the light conducting frame 8 and reflecting
from the reflector plate at the rear surface of the light conducting frame 8 to the
front direction so as to improve light intensity and uniformity (see Fig. 3)
[0012] As it is illustrated above, the variation of mesh density of the pattern 11 is in
a defined relation with a main axis along a line forming an angle of α (20° ∼70°)
with the X axis. The mathematical analysis is shown below:


[0013] Wherein An(x) represents ratio of area distribution at the center portion of the
pattern to the entire vision area (n=1, or 2), X represents the distance from the
light source 26 to the above center-portion.
[0015] Here, in another embodiment of the present invention shown in Fig. 5, an empty cavity
28 is formed in the light conducting frame 8 to reflect the light 29 which is excursing
away from the vision area 27 such that the excursed light 29 is effectively captured
into the vision area 27 thereby increasing the light intensity and improving light
uniformity thereof.
[0016] As for the steps of forming method of the present invention comprising the steps:
a) disposing a point light source 26 near the corner of a light conducting frame 8;
b) forming a specially designed pattern 11 on the year surface of the light conducting
frame 8 according to an area distribution function; and
c) forming several ramps 12, 14, 16, 22, 24 along the inner edge of the light conducting
frame 8 so as to capture and reflect the stray light trays 13, 15, 17, 23, 25 into
desired directions.
[0017] It emerges from the description of the above embodiments that the invention has several
noteworthy advantages, in particular:
1. Only one lighting element is used as a point light source instead of using a plurality
of lighting elements as in a conventional practice so as to save power consumption
and eliminate electromagnetic interference.
2. Several ramps are formed along the inner edge of the light conducting frame to
capture and reflect stray light rays into effective directions thereby further improving
the lighting efficiency and uniformity.
3. A lighting luminaire with specially designed reflector patterns caused it able
to use a point light source to serve an equivalent effectiveness of a planar light
source with a simple structure and a minimum cost.
[0018] Those who are skilled in the art will readily perceive how to modify the invention.
Therefore the appended claims are to be construed to cover all equivalent structures
which fall within the true scope and spirit of the invention.
1. A lighting luminaire using only one lighting element as a light source comprising:
a light conducting frame;
a unit lighting element disposed at a position near one comer of said light conducting
frame, to function as a point light source; and
a reflector plate provided at the rear surface of said light conducting frame,
a specially designed pattern is formed on the rear surface of said light conducting
frame according to an area distribution function by laser processing or plastic ejection
processing, and several ramps are formed along the inner edge of said light conducting
frame so as to further improve uniform distribution of output light.
2. The lighting luminaire of claim 1, wherein said point light source is disposed at
a position near one corner of said light conducting frame.
3. The lighting luminaire of claim 1, wherein the emitted light from said point light
source is conducted into said lighting luminaire along an extended structure of said
light conducting frame in diffused state before being outputted.
4. The lighting luminaire of claim 1 wherein said ramps formed along the inner edge of
said light conducting frame are with a tilted angle between 5° and 60° used for capturing
and reflecting biased light rays into effective directions thereby eliminating unlighted
dark space.
5. The lighting luminaire of claim 1, wherein an empty cavity is formed in said light
conducting frame to reflect the light which is excursing away from the vision area
such that the excursed light is effectively conducted into the vision area.
6. A forming method of a lighting luminaire using only one light source comprising the
steps:
a) disposing a point light source near the corner of a light conducting frame;
b) forming a specially designed pattern on the rear surface of said light conducting
frame according to an area distribution function; and
c) forming several ramps along the inner edge of said light conducting frame so as
to capture and reflect the stray light rays into effective directions.
7. The forming method of claim 6, wherein the variation of mesh density of said pattern
is in a defined relation with a main axis along a line forming an angle of α (20°∼70°)
with the X axis assuming:


wherein An(X) represents ratio of occupied area at the center portion of said
pattern to the entire vision area (n=1, or 2), X represents the distance from said
light source to the above center portion, L represents the distance from said light
source to the opposite comer of said light conducting frame, an(y) and bn(Y) are both
the functions of L, wherein






wherein D(L) is a function related to the depth of center point of said pattern
and L, for a common 1 mm thick plate, the average depth of a mesh is 20∼30µm, then
D(L) equals o.1, c2 equals 0.0179, c3 equals 0.01, c4 equals 0.5∼0.7.L is defined
as the distance from a point near the light source to the most distal point in the
vision area along the main axis forming a specified angle with the horizontal line
(X-axis).